How do centrifugal pumps differ from reciprocating pumps?

Centrifugal pumps are classified under dynamic displacement because they move fluid by converting mechanical energy into kinetic energy through the rotational motion of impellers. The design of these pumps relies on continuous flow, where the impeller creates a low-pressure area behind it, allowing fluid to be drawn into the pump and expelled at a higher velocity. This characteristic makes centrifugal pumps suitable for applications where a steady flow rate is required and they work efficiently with liquids of lower viscosity.

In contrast, reciprocating pumps operate on the principle of positive displacement. They function by trapping a fixed amount of fluid and then forcing it out of the pump chamber with each cycle. This method is often used for precise metering and handling of higher viscosity fluids.

The other choices refer to modes of operation or mechanics rather than the fundamental operating principle that distinguishes the two types of pumps. Steam-driven and belt-driven refer to how power is supplied to pumps but do not define the main mechanical action of centrifugal versus reciprocating pumps. Thus, dynamic displacement is the key differentiator for centrifugal pumps.